81812160 has 224 divisors, whose sum is σ = 306141120. Its totient is φ = 20496384.

The previous prime is 81812149. The next prime is 81812167. The reversal of 81812160 is 6121818.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (81812167) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 146602 + ... + 147158.

Almost surely, 2^81812160 is an apocalyptic number.

81812160 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81812160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (153070560).

81812160 is an abundant number, since it is smaller than the sum of its proper divisors (224328960).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81812160 is a wasteful number, since it uses less digits than its factorization.

81812160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 600 (or 584 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 27.

The square root of 81812160 is about 9045.0074626835. The cubic root of 81812160 is about 434.1161602326.

Adding to 81812160 its reverse (6121818), we get a palindrome (87933978).

The spelling of 81812160 in words is "eighty-one million, eight hundred twelve thousand, one hundred sixty".